Well, a little bit of alcohol every now and then as long as you are a fully mature adult isn't too bad. It sobers up the mind and when you're an adult you have to stay busy and work a lot. Pretty much it allows your body a bit to rest. But when you drink too much of it, it depresses your body too much and it impairs your brain function.
Alcohol, by itself, is not necessarily bad. Moderates amounts of alcohol, especially red wine, can be beneficial to a person's health. Alcohol can be a negative thing when people misuse it by self-medicating through alcohol consumption or over indulge in alcohol.
It dehydrates you. You know that headache you get after drinking? It's an extreme state of dehydration of the brain cells. It's your dehydrated brain shrinking away from the cranium. You need to take lots of water when you drink alcohol. Dehydration brings a lot of health problems.
Alcohol is not bad. In chemistry, alcohol is a family of chemicals used to dissolve other chemicals that normally do not dissolve in H20. Alcohol is a byproduct of fermentation and it is the main reason that a ship could sail for months without replenishing their supply before the invention of refrigeration. Without the invention of alcohol, the crew would dehydrate to death. In many places water was polluted and undrinkable so wine and beer were excellent substitutes that were safe to drink. Improvements in water purification and refrigeration invalidated the ancient necessity for alcohol so people used it for diversion. Things really got bad after the industrial revolution as workers become and extension of the machines and not human which lead to an increase in drunkenness. It allowed people to deal with the grinding poverty that was pervasive at the time. As technology advanced, alcohol shifted to more of a refined ritualistic cultural expression among the wealthy and a detrimental source of negative actions by the poor. So it is more a point of view.
also if you've seen the anti-smoking commercials, it basically does the same thing if you aren't smart about how much you consume. personally I hate the smell of wine and beer so I don't have a wish to drink any alcohol I know this makes me sound goody good but I'm just saying.